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Nonlinear Mode Crossing And Spontaneous Frequency Comb Generation In Driven Magnetic Nanodisks, Hasan Pi̇şki̇n
Nonlinear Mode Crossing And Spontaneous Frequency Comb Generation In Driven Magnetic Nanodisks, Hasan Pi̇şki̇n
Turkish Journal of Physics
Nonlinear magnetization dynamics in confined nanostructures provide a rich platform for fundamental studies and advanced spintronic applications. Here, we investigate the driven dynamics of a perpendicularly magnetized permalloy nanodisk using high-resolution micromagnetic simulations. In the linear regime, geometric confinement quantizes the uniform precession into discrete radial standing spin-wave (SSW) modes. As the excitation amplitude increases, the fundamental Kittel mode exhibits a pronounced nonlinear frequency shift relative to the higher-order SSW modes, ultimately leading to a critical mode crossing associated with nonlinear resonance overlap and the breakdown of modal orthogonality. Time-domain analysis reveals that strong mode hybridization governs the ensuing dynamics, …
Stress–Strain Behavior Of The High-Entropy Cantor Alloy Crmnfeconi Using A Deep Neural Network Potential, Nguyen Le Hoai Phuong, Le Huu Nghia, Huynh Khanh Van, Vo Khuong Dien, Nguyen Thanh Tien
Stress–Strain Behavior Of The High-Entropy Cantor Alloy Crmnfeconi Using A Deep Neural Network Potential, Nguyen Le Hoai Phuong, Le Huu Nghia, Huynh Khanh Van, Vo Khuong Dien, Nguyen Thanh Tien
Turkish Journal of Physics
Machine learning interatomic potentials (MLIPs) provide an efficient approach to large-scale molecular dynamics simulations of high-entropy alloys. In this work, an MLIP trained on AIMD data was developed for the CrMnFeCoNi Cantor alloy and validated against DFT calculations. In addition, we compared MLIP results with those obtained using the classical modified embedded atom method (MEAM)-based interatomic potential for the CrMnFeCoNi Cantor alloy. The model achieved energy and force RMSEs of 7.39 x 10-6 meV/atom and 4.46 x 10-3 eV/A, respectively. Tensile simulations demonstrated that the MLIP accurately reproduced the stress–strain response, elastic constants, and deformation mechanisms observed in DFT calculations. …
Spacer-Mediated Gold Nanocube Arrays For Edge-Localized Excitonic Enhancement In Monolayer Mos2, Abdullah Efe Yildiz, Emre Ozan Polat
Spacer-Mediated Gold Nanocube Arrays For Edge-Localized Excitonic Enhancement In Monolayer Mos2, Abdullah Efe Yildiz, Emre Ozan Polat
Turkish Journal of Physics
Plasmonic nanostructures offer an effective route for enhancing light-matter interaction in atomically thin semiconductors, whose optical response is intrinsically limited by their subnanometer active thickness. Here, we numerically investigate excitonic enhancement in monolayer (ML) Molybdenum Disulfide (MoS2) coupled to size-tuned gold (Au) nanocube arrays separated by thin aluminum oxide (Al2O3) and hexagonal boron nitride (h-BN) spacer layers. By varying the nanocube side length, the localized surface plasmon resonance is tuned across the visible spectral range to modulate the A- and B-excitonic transitions of monolayer MoS2.We show that the nanocube-size-dependent spectral redshift can be further controlled through the spacer material and …
Theoretical Construction Of Light Hexaquarks And Their Substantiation By Seven-Dimensional Representation Of Su(2) Group, Mayank Joshi, Shuchi Bisht, Navjot Hothi, Manish Bisht
Theoretical Construction Of Light Hexaquarks And Their Substantiation By Seven-Dimensional Representation Of Su(2) Group, Mayank Joshi, Shuchi Bisht, Navjot Hothi, Manish Bisht
Turkish Journal of Physics
This manuscript presents a theoretical approach to constructing light hexaquarks using up and down quarks. These light exotic hexaquarks are shown to exhibit a seven-dimensional representation of the SU(2) isospin group. Additionally, the isospin septuplet is developed along with the quintet, triplet, and singlet representations for these light exotic hexaquarks. These particles are essentially mesonic in nature and also satisfy the requirements of the Kronecker product. Furthermore, the physical characteristics and weights of the respective states are intrinsically provided for these light hexaquarks.
Selective Citation: The Systematic Omission Of Established Regional Literature, İrem Eli̇tez
Selective Citation: The Systematic Omission Of Established Regional Literature, İrem Eli̇tez
Turkish Journal of Earth Sciences
No abstract provided.
Integrated Assessment Of Groundwater Quality And Human Health Risks In A Semiarid Region Of Kemaliye (Türkiye), Veli̇ Keski̇n, Celaletti̇n Şi̇mşek
Integrated Assessment Of Groundwater Quality And Human Health Risks In A Semiarid Region Of Kemaliye (Türkiye), Veli̇ Keski̇n, Celaletti̇n Şi̇mşek
Turkish Journal of Earth Sciences
In this study, the hydrochemical characteristics, drinking water suitability, and potential human health risks of groundwater in the Karapınar region (Kemaliye, Erzincan, Türkiye), which has become a critical drinking water resource due to drought associated with climate change and the depletion of surface water resources, were investigated using an integrated multiparameter approach. Within the scope of the study, a total of 18 water samples, comprising 13 spring water samples and 5 groundwater samples obtained from wells, were collected during the dry season (October 2021) and analyzed for major ions, physicochemical parameters, nitrate, and trace elements. The suitability of the samples …
Editorial Note To The Article “Identification Of A Previously Unrecognized Listric Fault Beneath The Acıpayam Graben: Insights From Integrated Dinsar And Field Observations” [Turkish Journal Of Earth Sciences 35 (1) 2026 20-41], Orhan Tatar
Turkish Journal of Earth Sciences
No abstract provided.
Possible Fluid Contributions From Active Faults To Mercury Distribution In Surface Sediments Of The Gemlik Gulf And Health Risk Assessment, Erol Sari, M. Namik Çağatay, Tuğçe Nagi̇han Arslan Kaya, Zeynep Çeti̇n, Nuray Çağlar
Possible Fluid Contributions From Active Faults To Mercury Distribution In Surface Sediments Of The Gemlik Gulf And Health Risk Assessment, Erol Sari, M. Namik Çağatay, Tuğçe Nagi̇han Arslan Kaya, Zeynep Çeti̇n, Nuray Çağlar
Turkish Journal of Earth Sciences
The Gemlik Gulf, located in the eastern part of the Sea of Marmara (Türkiye), is recognized as a relatively contaminated marine environment, influenced by a variety of natural and anthropogenic inputs. A comprehensive geochemical study was performed to examine the distribution of total mercury (THg) in surface sediments and to elucidate the possible sources contributing to its accumulation. The analysis revealed that THg concentrations ranged from 485 to 6486 ng/g, with all measured values substantially exceeding the average shale background concentration of 400 ng/g, indicating significant enrichment. According to sediment quality guidelines, none of the samples exceeded the effects range …
Citation Scope And Scientific Relevance In An Event-Based Seismotectonic Study: Reply To The Comment By Elitez On Eski (2026), Semi̇h Eski̇
Citation Scope And Scientific Relevance In An Event-Based Seismotectonic Study: Reply To The Comment By Elitez On Eski (2026), Semi̇h Eski̇
Turkish Journal of Earth Sciences
No abstract provided.
Challenges, Trends, And The Role Of Lstm In Ai-Based Predictive Maintenance Of Electrolyzers For Solar Hydrogen Systems: A Review, Yani Koerniawan Kuatno, Muhamad Zahim Sujod
Challenges, Trends, And The Role Of Lstm In Ai-Based Predictive Maintenance Of Electrolyzers For Solar Hydrogen Systems: A Review, Yani Koerniawan Kuatno, Muhamad Zahim Sujod
Turkish Journal of Electrical Engineering and Computer Sciences
The transition toward low-carbon energy systems has increased interest in hydrogen as a clean energy carrier, with solar-driven water electrolysis emerging as a promising technology due to its high efficiency and compatibility with renewable energy sources. However, dynamic operating conditions and intermittent renewable input accelerate electrolyzer degradation, reducing reliability and system lifespan. Predictive maintenance (PdM), supported by artificial intelligence (AI), offers a data-driven approach to anticipate failures and improve operational durability. This review systematically investigates AI-based PdM approaches for electrolyzers, with an emphasis on long short-term memory (LSTM) networks and Internet of things (IoT) integration. Following PRISMA 2020 guidelines, 35 …
Dynamic Focal Loss Adjustment For Railway Defect Detection, Mehmet Koç, Ridvan Özdemi̇r, Ömer Gerek
Dynamic Focal Loss Adjustment For Railway Defect Detection, Mehmet Koç, Ridvan Özdemi̇r, Ömer Gerek
Turkish Journal of Electrical Engineering and Computer Sciences
Railway infrastructure is critical to the safe and efficient operation of transportation systems, and the early detection of defects is essential for preventing catastrophic failures. Automated defect detection methods are therefore crucial for maintaining continuous safety while reducing maintenance costs. Although Focal Loss is widely used in object detection under class-imbalanced conditions, its fixed α parameter may limit its effectiveness in detecting rare defects. In this study, we propose an adaptive α-tuned Focal Loss approach that dynamically adjusts class weights based on average precision (AP) values. By iteratively optimizing α without relying on gradient-based optimization, the proposed method improves the …
Relative Rate Observer-Based Online Tuning Mechanism For Single-Input Interval Type-2 Fuzzy Pid Controllers, Oqba Aldreiei, Cenk Ulu, Mert Can Kurucu, Müjde Güzelkaya
Relative Rate Observer-Based Online Tuning Mechanism For Single-Input Interval Type-2 Fuzzy Pid Controllers, Oqba Aldreiei, Cenk Ulu, Mert Can Kurucu, Müjde Güzelkaya
Turkish Journal of Electrical Engineering and Computer Sciences
The characteristics of the footprint of uncertainty (FOU) in interval type-2 membership functions (IT2-MFs) are crucial to the performance and robustness of interval type-2 fuzzy controllers (IT2-FCs). However, existing IT2-FC design approaches mostly use fixed FOU structures. This study proposes an online membership function (MF) adjustment mechanism for a single-input interval type-2 fuzzy PID controller (SIT2-FPID) that adjusts the FOU of the antecedent MFs and weights of the consequent MFs, respectively, to achieve high performance and robustness. The proposed online adjustment mechanism consists of a relative rate observer (RRO), a two-input rule-base adjustment system, and a first-order smoothing filter. The …
Cuip-X25: A Real-World Network Intrusion Dataset For Next-Generation Ai-Driven Security, Arshad Iqbal, Sohail Asghar
Cuip-X25: A Real-World Network Intrusion Dataset For Next-Generation Ai-Driven Security, Arshad Iqbal, Sohail Asghar
Turkish Journal of Electrical Engineering and Computer Sciences
The efficacy of artificial intelligence (AI) in intrusion detection systems (IDS) is critically dependent on high-fidelity training data. However, as detailed in the manuscript's literature review, existing benchmark datasets are predominantly synthetic, outdated, or imbalanced and fail to capture the complexity of the contemporary threat landscape. To bridge this gap, this study introduces CUIP-X25, a novel real-world cyber-attack dataset captured over a four-month period using a dionaea honeypot deployed on a public network. Unlike synthetic alternatives, this dataset provides an authentic representation of modern adversarial tactics, techniques, and procedures, encompassing 3.16 million real events across ten distinct attack categories, including …
Robust Load Frequency Control For Multiarea Electrical Power Systems Via Analytical Proportional-Integral-Derivative Plus Second Order Derivative Controller Design, Yavuz Güler, Mustafa Nalbantoğlu, Ibrahim Kaya
Robust Load Frequency Control For Multiarea Electrical Power Systems Via Analytical Proportional-Integral-Derivative Plus Second Order Derivative Controller Design, Yavuz Güler, Mustafa Nalbantoğlu, Ibrahim Kaya
Turkish Journal of Electrical Engineering and Computer Sciences
This research presents a proportional-integral-derivative plus second order derivative (PIDD2) controller design based on the Direct Synthesis Method (DSM) for load frequency control (LFC) of interconnected power systems. The parameters of the proposed PIDD2 controller are determined using the DSM, which offers an analytical approach for tuning. The design approaches have been developed specifically for single, two, and three-area power systems, encompassing nonreheated and reheated thermal turbines. In the proposed design method, the best values of PIDD2 controller parameters were found by using a multicriteria objective function that includes the integral of absolute error (IAE) and settling time. In response …
Boundary Layer Sliding Mode Control Strategy For Variable-Speed Compressor In Deep Freezers: Experimental Validation Of Energy Efficiency And Freezing Capacity, Sertan Aksoy, Kami̇l Çeti̇n, Sezai̇ Taşkin
Boundary Layer Sliding Mode Control Strategy For Variable-Speed Compressor In Deep Freezers: Experimental Validation Of Energy Efficiency And Freezing Capacity, Sertan Aksoy, Kami̇l Çeti̇n, Sezai̇ Taşkin
Turkish Journal of Electrical Engineering and Computer Sciences
This study presents the design and experimental validation of a nonlinear sliding mode controller developed for a deep freezer equipped with a variable-speed compressor. The proposed control strategy aims to minimize energy consumption while maintaining rapid and stable cooling performance under varying ambient conditions. A detailed thermal model of the deep freezer was established using an equivalent resistance–capacitance network representation, enabling precise analysis of temperature dynamics. The sliding mode-based control algorithm dynamically adjusts the compressor’s operating frequency according to temperature deviation, ambient conditions, and time-dependent factors, providing robust performance without requiring parameter retuning for different models. Beyond theoretical-based analysis, a …
Empowering Edge Intelligence Through Reparameterized Lightweight Transformers And Distributed Inference, Hosein Esmaeili, Mohammad Ali Afshar Kazemi, Reza Radfar, Nazanin Pilevari
Empowering Edge Intelligence Through Reparameterized Lightweight Transformers And Distributed Inference, Hosein Esmaeili, Mohammad Ali Afshar Kazemi, Reza Radfar, Nazanin Pilevari
Turkish Journal of Electrical Engineering and Computer Sciences
Deploying advanced transformer-based models on resource-constrained edge devices remains a significant challenge due to their high memory footprint and substantial compute requirements. In this paper, we propose a reparameterized transformer framework that integrates High-Rank Factorization (HRF) during training, layer merging at inference, and dynamic, load-balanced distributed inference across multiple devices. To further reduce resource usage, our framework supports mixed-precision quantization down to 4-bit, enabling flexible accuracy–latency–energy trade-offs. Experimental evaluations on the ESC-50 environmental sound dataset demonstrate that our method matches or exceeds the performance of larger baseline models while using 20–30% fewer parameters, achieving up to 48% latency reduction in …
Measurement-Aware Zero-Phase Iterative Learning Control For Robust Regulation Of Nonideal Boost Converters In Electric Vehicle Fast Charging, Aytaç Altan, Mohammed S. Alzaidi, Cağfer Yanarateş
Measurement-Aware Zero-Phase Iterative Learning Control For Robust Regulation Of Nonideal Boost Converters In Electric Vehicle Fast Charging, Aytaç Altan, Mohammed S. Alzaidi, Cağfer Yanarateş
Turkish Journal of Electrical Engineering and Computer Sciences
Integrating battery energy storage with DC-DC boost converters for electric vehicle fast charging exposes the regulator to ageing-induced parameter drift, periodic load pulses, and, critically, the nonidealities in the output-voltage sensing chain. This paper proposes a measurement-aware, zero-phase iterative learning control scheme for robust output-voltage regulation of a nonideal boost converter whose parameters are matched to those of a commercial Texas Instruments TPS6102x battery regulator. The controller combines an inner proportional-integral stabilizing loop with an outer zero-phase learning law that updates a feedforward correction based on the sensor-captured output trajectory; a forward-backward robustness filter suppresses the amplification of measurement noise …
Cover And Contents
Turkish Journal of Electrical Engineering and Computer Sciences
No abstract provided.
A Binary Multiobjective Hippopotamus Optimization Algorithm For Feature Selection In Phishing Website Detection, Fatima Belmessaoud, Sofiane Maza, Djaafar Zouache
A Binary Multiobjective Hippopotamus Optimization Algorithm For Feature Selection In Phishing Website Detection, Fatima Belmessaoud, Sofiane Maza, Djaafar Zouache
Turkish Journal of Electrical Engineering and Computer Sciences
Phishing website detection remains a major challenge in cybersecurity as attackers continuously develop new techniques to deceive users. Identifying the most informative features from large datasets is essential to improve classification accuracy while reducing computational complexity. Feature selection is therefore widely addressed using metaheuristic optimization techniques due to their flexibility and global search capability. In this study, we propose a Binary Multiobjective Hippopotamus Optimization Algorithm (B-MOHOA) for feature selection in phishing website detection. The proposed method simultaneously optimizes two conflicting objectives: maximizing classification accuracy and minimizing the number of selected features. Unlike many existing studies that mainly focus on transfer …
Range–Angle-Dependent Oam Beamforming With A Concentric Helical Circular Fda, Uğur Yeşi̇lyurt
Range–Angle-Dependent Oam Beamforming With A Concentric Helical Circular Fda, Uğur Yeşi̇lyurt
Turkish Journal of Electrical Engineering and Computer Sciences
Secure and spatially selective wireless transmission requires orbital angular momentum (OAM) beams that are confined to a specific range and angle, rather than propagating indefinitely along the beam axis. In this paper, a concentric helical circular frequency diverse array (CHCFDA) is proposed to generate range–angle-dependent OAM beams without requiring external phase shifters. The helical element positioning inherently provides the necessary interelement phase distribution through physical step height, while logarithmically increasing frequency offsets are applied across concentric rings—and optionally across individual elements—to eliminate range periodicity and achieve a single, well-focused OAM beam exclusively at the target location. Both linear and logarithmic …
Zoonotic Fish Parasites That Pose Risks To Human Health In Türkiye, Ahmet Özer
Zoonotic Fish Parasites That Pose Risks To Human Health In Türkiye, Ahmet Özer
Turkish Journal of Zoology
Fish-borne zoonotic diseases have been documented as the causative agents of considerable problems for humans on a global scale. This paper, for the first time, reveals the current zoonotic parasites of fish from wild and cultured hosts in marine, freshwater, and aquarium environments, as well as in native, endemic, and introduced hosts across different geographical areas and seas in Türkiye, based on published data to date. According to the latest global reports, zoonotic fish parasites in Türkiye are dominated by nematodes (17 species), trematodes (11 species), and cestodes (four species), followed by acanthocephalans (two species) and myxozoans (two species). The …
Toxicokinetics And Multibiomarker Assessment Of Coexposure To Sulfamethoxazole And Titanium Dioxide Nanoparticles In Cyprinus Carpio, Nazish Iftikhar, Rabeea Zafar, Imran Hashmi, Asma Jamil, Christopher Joseph Martyniuk, Munib Ahmed Shafique
Toxicokinetics And Multibiomarker Assessment Of Coexposure To Sulfamethoxazole And Titanium Dioxide Nanoparticles In Cyprinus Carpio, Nazish Iftikhar, Rabeea Zafar, Imran Hashmi, Asma Jamil, Christopher Joseph Martyniuk, Munib Ahmed Shafique
Turkish Journal of Zoology
The combined effects of pharmaceuticals and nanoparticles (NPs) on aquatic organisms remain insufficiently characterized. The present study examined toxicokinetics and multibiomarker responses of Cyprinus carpio (common carp) following exposure to sulfamethoxazole (SMX) and titanium dioxide (TiO₂) NPs. Juvenile fish were treated with SMX (25, 50, and 100 μg/L) alone and in combination with 1.5 mg/L TiO₂ NPs (96 h). TiO₂ NPs had a significant effect on the bioaccumulation of SMX in muscle tissues, with SMX reaching peak concentrations of 2286.54 ng/g in the 100 μg/L SMX + 1.5 mg/L TiO₂ NPs group after 72 h, compared to 1477.2 ng/g with …
Involvement Of Melatonin In The Regulation Of Reactive Oxygen Species Levels In Plants, Bariş Uzi̇lday, Oğuzhan Yilmaz, Tolga Yalçinkaya, Zehra Özgecan Tanyolaç, İsmai̇l Türkan, Rengi̇n Özgür Uzi̇lday
Involvement Of Melatonin In The Regulation Of Reactive Oxygen Species Levels In Plants, Bariş Uzi̇lday, Oğuzhan Yilmaz, Tolga Yalçinkaya, Zehra Özgecan Tanyolaç, İsmai̇l Türkan, Rengi̇n Özgür Uzi̇lday
Turkish Journal of Botany
Abiotic stress conditions impair plant metabolism partly by inducing the excessive production of reactive oxygen species (ROS). Melatonin, a multifunctional indoleamine, has emerged as an important regulator of plant responses to oxidative stress. This review highlights recent findings on the interactions among phytomelatonin, ROS homeostasis, antioxidant metabolism, photosynthetic protection, stress priming, and abiotic stress tolerance. We discuss how melatonin modulates the antioxidative response under diverse stress conditions and evaluate its effects on photosynthetic performance, ROS signaling, and membrane stability. Special attention is given to priming studies showing that melatonin pretreatment can improve stress tolerance. Emerging evidence from plant tissue culture …
Drought Priming Improves Waterlogging Tolerance In Alfalfa, But Less Effectively Than Waterlogging Priming, Gürkan Demi̇rkol, Ni̇lüfer Kara
Drought Priming Improves Waterlogging Tolerance In Alfalfa, But Less Effectively Than Waterlogging Priming, Gürkan Demi̇rkol, Ni̇lüfer Kara
Turkish Journal of Botany
Waterlogging severely restricts growth and productivity in alfalfa (Medicago sativa L.), necessitating effective strategies to improve stress tolerance. This study investigated whether drought priming or waterlogging priming could enhance tolerance to subsequent waterlogging stress in the alfalfa cultivar “Bilensoy-80”. Plants were subjected to drought priming, waterlogging priming, or no priming prior to progressive waterlogging stress for 0, 4, 8, 12, 16, and 20 days. Waterlogging priming consistently alleviated growth inhibition, maintained chlorophyll content, and reduced oxidative damage under prolonged stress. Drought priming was associated with partial cross-tolerance, particularly through improved root growth, plant water status, and oxidative stress responses, although …
On Families Of Finsler Metrics, İsmai̇l Sağlam, Ken'ichi Ohshika, Athanase Papadopoulos
On Families Of Finsler Metrics, İsmai̇l Sağlam, Ken'ichi Ohshika, Athanase Papadopoulos
Turkish Journal of Mathematics
In this paper, we answer some natural questions concerning symmetrisation and more general combinations of Finsler metrics, with a view to applications to Funk and Hilbert geometries and metrics on Teichmüller spaces. The metrics on Teichmüller space that we consider are the Thurston metric and the earthquake metric, both introduced by Thurston. The first metric has been thoroughly studied over the last couple of decades, and the second over the last few years. The Funk metric and its symmetrisation, the Hilbert metric, are classical metrics that have been investigated in the contexts of hyperbolic geometry and geometric function theory and, …
A Note On The Periodic Orbits Of Wolbachia Spread Dynamics In Mosquito Populations In Periodic Environments, Jose S. Cánovas
A Note On The Periodic Orbits Of Wolbachia Spread Dynamics In Mosquito Populations In Periodic Environments, Jose S. Cánovas
Turkish Journal of Mathematics
We consider the periodic model introduced by B. Zheng and J. Yu, and disprove the conjectures on the number of periodic orbits the model can have. We rebuild the conjecture to prove that for periodic sequences of maps of any period, the number of nonzero periodic trajectories is bounded by two.
Characterizations Of Bi-Riordan Arrays, Nai̇m Tuğlu, Fatma Yeşi̇l Baran
Characterizations Of Bi-Riordan Arrays, Nai̇m Tuğlu, Fatma Yeşi̇l Baran
Turkish Journal of Mathematics
In this study, we introduce the concept of a bi-Riordan array. As part of this construction, we define new composition and power operations. We then establish an analogue of the well-known fundamental theorem of Riordan arrays (FTRA), which we call the fundamental theorem of bi-Riordan arrays. Next, we show that the product of two bi-Riordan matrices is again a bi-Riordan matrix. Using this product structure, we prove that the set of bi-Riordan matrices forms a monoid.
Exponential Stability For A Strongly Damped Wave Equation With Distributed Internal Delay, Manal Alotaibi, Nasser-Eddine Tatar, Waled Al-Khulaif
Exponential Stability For A Strongly Damped Wave Equation With Distributed Internal Delay, Manal Alotaibi, Nasser-Eddine Tatar, Waled Al-Khulaif
Turkish Journal of Mathematics
This paper investigates the exponential stability of a strongly damped wave equation subject to an internal distributed time delay. Two distinct analytical frameworks are developed: the first employs a modified energy method based on auxiliary functionals, while the second introduces a transformation that rewrites the delay term as the derivative of a convolution integral. Both approaches yield explicit decay conditions and establish exponential convergence of the energy under weaker assumptions on the damping coefficient and the delay kernel. Notably, the transformation method allows for a wider class of admissible delay weights than those permitted by classical techniques. Numerical simulations based …
A Delayed Siamr Prostate Cancer Model With Vertical Transmission And Treatment: Stability Analysis And Numerical Simulation, Hüseyi̇n Demir, İnci̇ Çi̇li̇ngi̇r Süngü, İbrahi̇m Keles
A Delayed Siamr Prostate Cancer Model With Vertical Transmission And Treatment: Stability Analysis And Numerical Simulation, Hüseyi̇n Demir, İnci̇ Çi̇li̇ngi̇r Süngü, İbrahi̇m Keles
Turkish Journal of Mathematics
In this paper, we propose and analyse a delayed-compartmental mathematical model of prostate cancer dynamics that incorporates vertical transmission and therapeutic intervention. The population is stratified into five compartments: susceptible (S), infected/virally activated (I), asymptomatic infectious under treatment (A), malignant untreated (M), and recovered (R). A discrete time delay τ > 0 is introduced in the force-of-infection term to model the age-dependent onset of susceptibility in middle-aged adult males. Vertical transmission of viral etiology at a rate qΛ ensures that a fraction of newborns enter the infected compartment directly, rendering the disease persistent regardless of the basic reproduction number R₀. We …